Defeating CIFS file caching on Windows / forcing "refresh"

windows samba cifs
Ben Jackson picture Ben Jackson · Nov 1, 2010 · Viewed 7.8k times · Source

I'm modifying files on a UNIX system and accessing them on a Windows box. The server runs samba and there is some amount of caching done by the client. When I modify the file on the UNIX side, the only reliable way to see the new version of the file is to right click in Windows Explorer and select "refresh".

I'm looking for the Windows API equivalent of right-clicking in Windows Explorer and selecting "refresh". There are other questions on SO about sending a message to Explorer to cause it to refresh, but that's not what I want: I don't care about the contents of the Explorer window and I would prefer to not even need one open to the target directory. I just want to integrate the cache-defeating effect into my program so I avoid seeing stale data.

Answer

Robie Basak picture Robie Basak · Nov 1, 2010

CIFS includes a notification system for updates. Explorer registers for this, and will reflect any changes that Samba sends it. I'm not aware of any other API mechanism to tell Windows that it needs to do a refresh.

Samba supports Linux inotify, so it should automatically pick up any changes to folders that Explorer is displaying and send Explorer updates.

Are you using a recent-enough version of Samba, and has Samba been built with inotify support? This is obviously Linux only. For another Unix, you could implement equivalent functionality. The relevant code is in smbd/notify_internal.c.

Related questions

HTML link to directory in a Samba share, that works on Internet Explorer 7/8

I want my HTML page to link to a directory in a Samba share (protocol SMB/CIFS Windows share). In my HREF I wrote file://server/Share2/folder3 Most browsers handle it fine (mount the share and open a file …

Read More
BASH: Strip new-line character from string (read line)

I bumped into the following problem: I'm writing a Linux bash script which does the following: Read line from file Strip the \n character from the end of the line just read Execute the command that's in there Example: commands.…

Read More
What is the meaning of these Windows Environment variables: HOMEDRIVE, HOMEPATH, HOMESHARE, USERPROFILE

What is the meaning of these Windows Environment variables: HOMEDRIVE, HOMEPATH, HOMESHARE, and USERPROFILE? Who set them? When? Who use them? For doing what? How the configuration of the samba server modify these variables?

Read More